Ronald White went missing in 2016, but because of a job that involved frequent travel, no one figured he had actually been dead this whole time. (Photo courtesy of WFAA-TV)

Doris Stevens was used to getting a call from her son Ronald Wayne White at least twice a month. The U.S. Navy veteran, who worked for a defense contractor and traveled frequently, would often contact his mother from wherever he was in the world.

The last time Stevens spoke with her son was in 2016 and when she called him on his birthday the following year, she knew something was wrong. Tragically it turns out White was found dead in his DeSoto, Tex., apartment last week.

“I can’t hardly cope with it, to be honest with you,” Stevens told Dallas station WFAA. “I can’t get past three years. … I can’t hardly deal with it.”

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The actual mystery to the story is the length of time between Stevens losing contact with her son and the discovery of his body earlier this week.

White had disappeared without a trace and Stevens, who lives in Long Island, N.Y., had no clue how to find her son. Searches of places he lived before turned up nothing and she says she had no money to hire a private investigator. Further, police told her that since he traveled so often for work, they had no reason to pursue his lack of communication as the basis for a missing persons case.

Maintenance workers in the apartment complex were sent to investigate units where tenants were not using water. When they forced the door open, they found White lying on his kitchen floor. An autopsy determined he had been dead for at least three years. He would have been 51 at the time of his death.

“When the medical examiner told me three years, my knees gave away. Three years? And that’s what I can’t get past in my brain. I can’t get past three years,” said Stevens. “My biggest question is, how in the world could my son have been dead in that apartment and nobody knows anything?”

White, who lived alone and had divorced 20 years ago, had a month-to-month lease in his apartment, which was automatically withdrawn from his account as a Navy vet. He would not necessarily have to send a rent check or show up at a leasing office. The apartment sits in a relatively obscure corner of the complex and is well-sealed, so any odor coming from a decaying corpse was unlikely to escape.

A downstairs neighbor did complain about liquid coming through the ceiling, but after it stopped, maintenance didn’t inspect it any further once they knocked on White’s door and got no answer.

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“What I can tell you is it is very clear when officers entered that he had been there for a while,” Det. Pete Schulte, with the DeSoto Police Department told WFAA.

He added that medications for diabetes were found in the apartment and that White’s family confirmed he was a diabetic.

“The way he was found, the way the apartment was arranged and so forth, there was zero indication of foul play,” Schulte said.

A medical examiner is running toxicology tests to determine an official cause of death.

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White’s pickup truck was found in the DeSoto Town Center’s parking garage which is a public parking area, so he would have received no notifications that the vehicle needed to be moved, or have gotten any parking tickets. The truck was covered in dust and leaflets.

The question of how White could have laid dead in his apartment for three years with not one person — not even the property management — noticing remains puzzling. A spokesperson for the apartment complex released this statement.

“Our thoughts and prayers are with the family of Mr. White during this difficult time. 

Mr. White was frequently out of the country and his bills were paid through automatic withdrawals from his accounts. Our maintenance personnel discovered his body when they identified and responded to a service issue at his apartment. We are cooperating with the police as they investigate this incident.”